From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7486B48987C; Mon, 31 Aug 2026 14:04:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788185052; cv=none; b=rb6cz06LymZOFGAens8ar+9dBMX+369pB9MZZIdhqqi422YvNRrP1OuFemYKTHwpbDS1LvD7+pgi9jJDd33IhyjjM6Bo2LleHm4dOyOWFR4scKnphpQLCuSdaXhKKgaucLyrcm/xkokYraWWG7RmxMaM80MFZauSYbFnDFBwj1k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788185052; c=relaxed/simple; bh=COII7TgoEgR2kJhNJetVK/wXXblb9czVeTpEUMBI6TM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=k2c/OCKE+nidlFScZyf4saROgWCQv5JNb57yiD0Vrw18yXQGdXcyHbS6eKL2oben4ztx1KXH2k2CKskWYaghMpVBOTdwkF67Qh2qA5Yy8bPq2aDoqCWfpNZMdI0MpMATL/DljHe4FIfjcgbIllgrrCPuWhE40DPHpH656nQw4ps= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=vY7aFjxC; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="vY7aFjxC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CEC871F000E9; Mon, 31 Aug 2026 14:04:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788185050; bh=tAu8H5BXO3M5tOhWx3hsRa21b2V4jjpAA5Ic4Ghw2Rc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=vY7aFjxCIZ3zmE9RBdxrFhTq2eJjc2Qjy9wQq+Apibt7cv0KIu3/iksoXYwfQKUhC lsLZ1Ary1sZrkJVjN3vvDQ54LEY4vn2yxvHFuNqKsAHiaHrQo8v1tztpO9yD5a//ZV VkKTpLeoEwkL0YvK+jmWnzMmeKcf7fJyfLFdYs14= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Enrik Berkhan , Michael Zaidman , Jiri Kosina , Sasha Levin Subject: [PATCH 5.15 37/69] HID: ft260: wake up device from power saving mode Date: Mon, 31 Aug 2026 15:35:10 +0200 Message-ID: <20260831133400.367295659@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260831133358.601894154@linuxfoundation.org> References: <20260831133358.601894154@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Zaidman [ Upstream commit 4b3da6853a619a952e8caf2e8393264dd42ffa27 ] The FT260 can enter a power saving mode after being idle for longer than 5 seconds. When being woken up from power saving mode by an I2C write request, a possible NACK is not correctly reported by the controller. As a workaround, the driver will issue an I2C status report two times in ft260_xfer_status() after the chip has been idle for more than 5s. Co-developed-by: Enrik Berkhan Signed-off-by: Enrik Berkhan Signed-off-by: Michael Zaidman Signed-off-by: Jiri Kosina Stable-dep-of: bf3e39df3a39 ("HID: ft260: fix stack-use-after-return write in I2C read race") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/hid/hid-ft260.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) --- a/drivers/hid/hid-ft260.c +++ b/drivers/hid/hid-ft260.c @@ -31,6 +31,8 @@ MODULE_PARM_DESC(debug, "Toggle FT260 de #define FT260_REPORT_MAX_LENGTH (64) #define FT260_I2C_DATA_REPORT_ID(len) (FT260_I2C_REPORT_MIN + (len - 1) / 4) +#define FT260_WAKEUP_NEEDED_AFTER_MS (4800) /* 5s minus 200ms margin */ + /* * The ft260 input report format defines 62 bytes for the data payload, but * when requested 62 bytes, the controller returns 60 and 2 in separate input @@ -237,6 +239,7 @@ struct ft260_device { struct completion wait; struct mutex lock; u8 write_buf[FT260_REPORT_MAX_LENGTH]; + unsigned long need_wakeup_at; u8 *read_buf; u16 read_idx; u16 read_len; @@ -306,6 +309,20 @@ static int ft260_xfer_status(struct ft26 struct ft260_get_i2c_status_report report; int ret; + if (time_is_before_jiffies(dev->need_wakeup_at)) { + ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, + (u8 *)&report, sizeof(report)); + if (unlikely(ret < 0)) { + hid_err(hdev, "failed to retrieve status: %d, no wakeup\n", + ret); + } else { + dev->need_wakeup_at = jiffies + + msecs_to_jiffies(FT260_WAKEUP_NEEDED_AFTER_MS); + ft260_dbg("bus_status %#02x, wakeup\n", + report.bus_status); + } + } + ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, (u8 *)&report, sizeof(report)); if (unlikely(ret < 0)) {